69 | 4 things you can do to provide better care to dogs with tracheal collapse

PodcastRespiratory
Written By Laura Jones

If you’ve ever seen an overweight Yorkie honking like a goose,
then there’s a good chance you’ve dealt with tracheal collapse before.

 

It’s a progressive and often challenging condition to manage and can make breathing a real struggle for our patients. But by managing these patients well and providing client education and support, we can make a significant difference to these patients.

Plus, in severe cases, there are some cool interventions we can perform - and therefore skills we can use - too!

Today, we’re going to break down what tracheal collapse is, who the patients most at risk are, how to stabilise, diagnose and treat them, and what we can do as nurses to support these cases.

Let’s take a closer look at the lower airways for a second.

The trachea is made up of C-shaped cartilage rings connected by a band of muscle and connective tissue known as the dorsal membrane. Between each tracheal ring is a ring of smooth muscle.

Though the incomplete tracheal rings are beneficial for movement as the trachea is more flexible, it does mean that the airways aren’t as well supported, and there’s the potential for tracheal narrowing or collapse.

The trachea bifurcates at the carina into the left and right mainstem bronchi, which each supply a lung. These bronchi continue to divide into lobar bronchi and progressively smaller bronchioles until they become a terminal bronchus with an attached alveolar sac.

The trachea and bronchi have the same structure, and that’s important to note, because it means that patients don’t just get collapse of the trachea - the bronchi can be affected, too.

Tracheal collapse, as the name suggests, is the progressive collapse or ‘flattening’ of those C-shaped cartilage rings.

Patients can have a dynamic collapse (where the collapse changes, for example, collapse occurs when the patient coughs) or a static (permanent) collapse. 

We can see collapsed areas in the extrathoracic trachea, intrathoracic trachea, or both. Cervical disease causes the trachea to collapse on inspiration, and intrathoracic disease causes the trachea to collapse on expiration.

Dynamic tracheal collapse results from differing pressures inside and outside of the trachea during breathing, causing periodic collapse.

Which patients develop tracheal collapse, and why?

Tracheal collapse is classically seen in small and toy breed dogs. Yorkshire terriers in particular, are very commonly diagnosed, as are Pomeranians, Chihuahuas, Toy Poodles and even Pugs. Though, in theory, any breed can be affected (and so can cats, though this is very rare).

There is surprisingly little evidence on factors causing tracheal collapse, though genetics are likely to play a role, given the strong breed predisposition. There is also some evidence that the GAG (glycosaminoglycan - the same substance that protects the bladder lining and is depleted in FIC cats) content is lower in dogs with tracheal collapse.

How does bronchial collapse differ from tracheal collapse?

Bronchial collapse, or bronchomalacia, is a similar condition with uncertain cause and progression. It has been linked to airway inflammation in some cases but not all. 

We do know that these patients have weakness of their bronchial walls and that it is commonly seen in conjunction with tracheal collapse (but not always). It can occur in dogs of any age and in both small and large breeds. 

Ok, so that’s what tracheal collapse is and the patients we see it in. How do these patients present? What are their clinical signs?

The classic sign of tracheal collapse is a chronic, loud cough. It’s a very distinctive cough described as a ‘goose honking’ cough, and it’s caused by:

  • Mechanical irritation from airway collapse

  • Chemical stimulation from inflammation or secondary infection

  • Excitement, stress, heat or pressure on the trachea (e.g. pulling on a collar).

These signs are progressive and depend on the severity of the patient’s disease and the presence of any exacerbating factors (like heat, stress, exercise or obesity).

Severely affected patients commonly present in respiratory distress or may even have syncope episodes due to airway obstruction. These patients require immediate stabilisation with oxygen and a hands-off approach initially, alongside antitussives and sedation as needed. I really like butorphanol for its antitussive and mildly sedative effects - if your vet agrees, it’s a great option to take the edge off of a stressed respiratory patient.

In very severe cases, endotracheal intubation may be required, though this will only work if the collapse is cranial and in an area where the ET tube will reach.

The next step once our patient is stabilised? Diagnosis.

Tracheal collapse is diagnosed based on a combination of clinical history, physical examination and diagnostic imaging.

Radiography can show tracheal narrowing in some cases, but an intermittent or dynamic collapse could easily be missed on a static image. For that reason, we prefer to use either fluoroscopy or endoscopy (or both) for assessment.

Let’s take a look at fluoroscopy.

Fluoroscopy is a live video X-ray. It’s used to look for dynamic changes since it records in real time, rather than taking one image only. We can examine the trachea both on inspiration and expiration, looking for changing collapse as the patient breathes.

What about endoscopy?

A tracheobronchoscopy allows us to directly visualise the collapsed trachea and grade its severity, and perform sampling such as a broncho-alveolar lavage (BAL) to check for secondary infections.

It’s not without risk since we’ll need to intubate the airway with the endoscope and, in most cases, extubate the patient (due to their small ET tube size). This carries a high risk of desaturation since we’re further compromising the airway of an existing respiratory patient.

How to grade a tracheal collapse patient

The grade we give them depends on the extent of the tracheal flattening seen on endoscopy:

  • Grade I: 25% of the lumen is obstructed

  • Grade II: 50% is obstructed

  • Grade III: 75% is obstructed

  • Grade IV: 90% of the lumen is obstructed.

Once your patient has their diagnosis, it’s time to think about treatment.

Treating tracheal collapse depends on the type and severity of the patient’s collapse. Our goals are to limit disease progression and control clinical signs to improve the patient’s quality of life as much as possible.

This can be achieved medically in most cases, though some patients do require surgery or interventional procedures.

Let’s look at medical management first.

Medical management aims to stop the self-perpetuating cycle of coughing causing collapse, which causes inflammation, which causes further coughing and collapse.

Cough suppressants and anti-inflammatory medications are commonly used alongside antibiotics where needed if a secondary infection is present. Butorphanol and codeine are common antitussives and can be helpful in these patients.

Oral steroids may decrease inflammation and therefore also improve coughing, though they can cause patients to gain weight, which in turn worsens coughing. If they are needed, the lowest effective dose should be used.

There is some suggestion that maropitant can also be used in tracheal collapse patients to improve signs, and cough did decrease with its use in one study looking at chronic bronchitis patients.

Alongside medications, weight management, careful exercise, and avoiding neck collars are recommended.

In severe cases, however, medical management might not be enough.

If permanent intervention is needed, we have two options: tracheal stent placement or extratracheal ring placement. Both of these will resolve honking and obstruction, but they don’t necessarily ‘fix’ the cough - and of course, like any procedure, they’re not without risk.

Tracheal stents are relatively easy to place. They’re made of a thin wire mesh which lines the trachea and holds it open, and they can be placed minimally invasively via bronchoscopy and fluoroscopy. Risks include stent fracture, improper fit, dislodgement, infection or granulation tissue formation.

Extratracheal rings are permanent rings surgically placed around the outside of the trachea. Unlike stents that sit inside the tracheal lumen, with rings, the trachea is sutured to them and ‘pulled’ open. However, they’re not suitable for every patient - they only work in patients with extrathoracic disease, and they also carry the risk of laryngeal paralysis, due to surgical trauma/damage to the laryngeal nerve.

And what about nursing? How can we help these patients?

There are a few important nursing considerations for tracheal collapse patients, including:

1: Supportive care and minimising stress

Any patient presenting in respiratory distress needs prompt triage and stabilisation, and it’s usually us who are best placed to do this. Patients should be assessed quickly, and oxygen and anxiolytics provided as appropriate.

After initial stabilisation, minimising stress is really important - particularly when trying to examine these patients, remove them from oxygen, or take them outside to defecate/urinate.

2: Weight management

Many patients with tracheal collapse are overweight. Weight management is an essential step in their management since this will decrease coughing. 

Aim for a gradual weight loss of up to 1-2% bodyweight per week, and reassess the patient regularly.

3: Client education and support

Client education is vital to prevent further episodes of respiratory distress and reduce the patient’s clinical signs. 

Advise them to use a harness for walking instead of a neck collar, make a nutritional plan for at-home weight loss as we’ve just mentioned, and talk to them about preventing overexcitement or exertion, particularly in warm weather.

 Addressing environmental allergens or toxins (if possible) is no bad thing either, though it isn’t directly related to tracheal collapse.

Lastly, some patients will be treated with inhaled steroids rather than systemic anti-inflammatories. These are given via a metered dose inhaler and a spacer chamber with an attached face mask, which does take some getting used to - both for the patient and their family! 

Training the patient to accept the inhaler and face mask device without stress is a vital and often overlooked step - and one we’re great at supporting. These patients will often need ongoing medication, and if a patient becomes really stressed by it, that’s the last thing we need - so a slow, gradual introduction with lots of positive reinforcement is key.

4: Post-stent placement care (if applicable)

Placed a stent? These patients need careful monitoring, especially in the immediate post-operative period. Monitor them closely for signs of stent fracture, movement or other complications, and intervene as needed - with an emergency kit on-hand nearby.

So there you have it - the ins and outs of tracheal collapse and the exact care these patients need! Tracheal collapse can be challenging to manage, but with the right combination of triage and stabilisation, medical management, nursing care, and client support, we can help these patients have much happier lives.

Whether it’s helping with weight loss, adjusting medications, or training owners to use inhalers, we play an essential role in improving the quality of life for these patients.

Did you enjoy this episode? If so, I’d love to hear what you think. Take a screenshot and tag me on Instagram (@vetinternalmedicinenursing) so I can give you a shout-out and share it with a colleague who’d find it helpful!

Thanks for learning with me this week, and I’ll see you next time!

References and Further Reading

Laura Jones
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